The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be embodiments of the invention.
In recent years, there has been explosive growth in the number of portable and handheld devices that include but are not limited to sensors such as accelerometers, gyros, magnetometers, altimeters, force, and/or pressure sensors. Examples of such devices include smart phones, cell phones, gaming devices, and wearable devices or “wearables.” A large number of wearables target health and fitness applications where steps taken and flights of stairs taken by device users are tracked utilizing accelerometers and altimeters. Most health and fitness wearables on the market today may track one or more of the following: steps taken, number of stairs taken, heart rate, movement activity, and sleep patterns. These devices generally utilize accelerometers, altimeters, light sources and sensors, and voltage sensors to sense and detect the parameters they measure and track.
In physical therapy rehab, training to improve physical and athletic performance, and training for injury reduction, there is often a need to engage or contract a specific muscle or muscle group to target their use during exercise, or to engage a specific muscle or muscle group before and throughout a movement to provide support. However, without a feedback device on the targeted muscle or muscle group, it may be difficult for the subject to isolate and engage the muscle or muscle group. While the subject may engage the targeted muscle or muscle group before the movement, the subject may relax during the movement. Without a feedback device providing continuous feedback, it may be difficult to identify if the subject engaged the muscle or muscle group before and throughout the movement. An example of a muscle group and a movement in which engaging the target muscle group before and throughout the movement may include engaging the core muscles before and throughout standing up from a seated position during a episode of back pain.
In therapy rehab, isolating muscles is important for muscle re-education that is often required after injury or surgery. Isometric exercises are physical exercises in which muscles are caused to act against each other or against a fixed object. Isometric exercises may involve engaging or contracting a muscle or muscle group and keeping it engaged for a period of time. For some applications, the period of time may be 30 seconds. For some applications, the period of time may be longer than 30 seconds, For other applications it may be shorter than 30 seconds. It may be beneficial when doing isometric exercises to have a means to confirm that the target muscle or muscle group is indeed engaged during the exercise and a minimum degree of engagement intensity is being maintained. In isotonic exercises, the muscles maintain the same tension throughout the exercise. If a target muscle in an isotonic exercise can be engaged before and through the exercise, the exercise may be more beneficial for the target muscle and further aid the subject's neuromuscular system with muscle education or re-education. An appropriate feedback device for isometric and isotonic exercises that can provide an indication of engagement intensity can be beneficial for improving the quality and thus, the benefits of said exercises. Quantitative feedback can also provide motivation for the subject to make measurable improvements or compete with a partner.
For performance training and injury reduction training, both isometric and isotonic exercises may play important roles. The ability to engage specific target muscles may increase the effectiveness of such exercises. Further, with an appropriate training regimen, a connection between the brain and the target muscle may be established and developed to build motor memory for conscious deliberate use of that muscle and eventually an automatic use of that muscle in specific tasks.
In the exercise settings of a therapy clinic, in-home therapy with a therapist and patient, and in gym training, there may be need to quickly transition exercises emphasizing one muscle or muscle group to another. For example, in one exercise set the core muscles may be the target muscle group. In the next exercise set, the gluteus maximus may be the target muscle. The ability to move the monitoring device quickly and conveniently may be important in some applications.
One approach to monitoring muscle engagements uses electromyography (EMG). Electromyography measures electrical activity in a muscle. One form of EMG, needle EMG, utilizes insulated needles each with a small region of bare metal that is inserted into a muscle to make direct electrical contact that the muscle. Due to its invasive nature, needle EMG is not widely used in therapy and gym settings. Another form of EMG is called surface EMG where electrodes are attached to the surface of the skin over the region of the target muscle. The good electrical contact needed between the electrodes and the skin may be achieved in different ways. Conductive gels may be used on the electrodes as they are held against the skin using tape.
Some of the newer electrodes have built-in adhesives that stick to the skin. These sticky surface electrodes need to be replaced after a number of uses. Surface EMG is not as accurate as needle EMG but sufficient for most clinical and gym applications. Sticky surface electrodes, while being much simpler than the needle electrode counterpart may be a bit cumbersome to move from one muscle or muscle group to another.
Another approach to monitoring muscle engagements uses ultrasound. While potentially being very accurate, ultrasound probes are expensive and require gels to make effective contact to the skin. Implementations to date make body movement while monitoring a muscle difficult.
The wearable device and app that runs on a smart device or dedicated device that has been described in Incorporated Patent References may be used to monitor the relaxed and engaged status of a muscle or muscle group, and provide immediate feedback; can be quickly moved from one muscle or muscle group to another when held against the body with an appropriate attachment device, for example, a belt or strap; does not require any gels or special probes requiring direct contact to the skin; and can be used over most clothing. In applications where more than one muscle or muscle group must be monitored during the same exercise, multiple wearable devices may be used.
Protected movements involve movements which benefit the user when a target muscle is engaged before and through the movement or critical aspects of the movement. Unprotected movements involve movements in which a target muscle is not contracted adequately to have made the movement a protected movement. Protected movements may benefit a user by improving an exercise, improving a rehab movement, result in a movement with less likelihood of injury, improve an athletic movement, contribute to procedural memory development for use of the target muscle in the movement, or have another desirable short term or long term result. Protected qualifying movements are protected movements.
In this patent application, techniques and algorithms to improve the performance and utility of the wearable device and system are described.